Ambrx, Saying Thanks to its Rivals, Rides Wave of Interest in “Empowered” Antibodies

There’s no denying that Ambrx CEO Steve Kaldor is a competitor. Still, when I visited him in his San Diego office a few weeks ago, Kaldor was happy to tip his cap to a couple of trail-blazing competitors who have done a lot over the past year to make his life easier.

Ambrx ended the year with about the same number of employees (80), the same amount of cash in the bank as it did a year ago (about $60 million), a new partner in Pfizer, and enough money to operate for multiple years. And while some of that is certainly Ambrx’s own doing, Kaldor sent out a big thank you to Roche and Waltham, MA-based ImmunoGen (NASDAQ: IMGN).

Why? Those companies have built up a body of evidence that suggests they may have the first “empowered” antibody for cancer that has a chance to become a commercial hit. The drug, called T-DM1, combines the ability of an antibody to seek out diseased cells, with a potent toxin that gives the treatment extra tumor-killing kick. This is supposed to be one of the new frontiers in the world of antibody drugs, which have been around more than a decade and have created a market worth an estimated $30 billion a year. While scientists have dreamed for three decades about making more potent versions of plain antibodies, most efforts have fizzled, usually because the toxin broke off and floated in the bloodstream before it could get to the target, causing side effects.

Ambrx has been around since 2003 and has raised more than $106 million in venture capital to engineer protein drugs with new properties that can make them last longer in the blood, or enable them to carry those potent little toxins. But this was the year Ambrx amped up its effort to make so-called “empowered antibodies” that are sometimes called antibody drug conjugates. About one-third of Ambrx’s staff are now working on empowered antibodies, and half of the company’s resources are going toward antibodies, Kaldor says. One of the reasons is that pharma companies have seen the T-DM1 data and want to find a partner who can help them get in the game, too.

Steve Kaldor

“It’s been amazing to see. T-DM1 is floating a lot of other boats,” Kaldor says.

He adds: “It’s been a long haul, but across the industry, people are coming to the realization that if they want to be in the second-generation antibody space, they have to do antibody-drug conjugates.”

One other company, Bothell, WA-based Seattle Genetics, has offered some more evidence to support the “empowered antibody” approach. That company (NASDAQ: SGEN) has produced some compelling data that its drug can cause complete remissions in Hodgkin’s disease patients. The data was strong enough that Seattle Genetics was able to retain 100 percent of the U.S. commercial rights to the drug, while enticing Millennium: The Takeda Oncology Company to pay $60 million in upfront cash for co-promotion rights in all countries except the U.S. and Canada.

“Seattle Genetics clearly had a lot of leverage,” Kaldor says. “People are really craving to get into the space.”

Ambrx doesn’t say much specifically about how this is really affecting its business. The latest … Next Page »